/* Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.activiti.rest.service.api.history;

import org.activiti.engine.ActivitiIllegalArgumentException;
import org.activiti.engine.HistoryService;
import org.activiti.engine.history.HistoricProcessInstanceQuery;
import org.activiti.engine.impl.HistoricProcessInstanceQueryProperty;
import org.activiti.engine.query.QueryProperty;
import org.activiti.rest.common.api.DataResponse;
import org.activiti.rest.service.api.RestResponseFactory;
import org.activiti.rest.service.api.engine.variable.QueryVariable;
import org.activiti.rest.service.api.engine.variable.QueryVariable.QueryVariableOperation;
import org.springframework.beans.factory.annotation.Autowired;

import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;

/**
 * @author Tijs Rademakers
 */
public class HistoricProcessInstanceBaseResource {

    private static Map<String, QueryProperty> allowedSortProperties = new HashMap<String, QueryProperty>();

    static {
        allowedSortProperties.put("processInstanceId", HistoricProcessInstanceQueryProperty.PROCESS_INSTANCE_ID_);
        allowedSortProperties.put("processDefinitionId", HistoricProcessInstanceQueryProperty.PROCESS_DEFINITION_ID);
        allowedSortProperties.put("businessKey", HistoricProcessInstanceQueryProperty.BUSINESS_KEY);
        allowedSortProperties.put("startTime", HistoricProcessInstanceQueryProperty.START_TIME);
        allowedSortProperties.put("endTime", HistoricProcessInstanceQueryProperty.END_TIME);
        allowedSortProperties.put("duration", HistoricProcessInstanceQueryProperty.DURATION);
        allowedSortProperties.put("tenantId", HistoricProcessInstanceQueryProperty.TENANT_ID);
    }

    @Autowired
    protected RestResponseFactory restResponseFactory;

    @Autowired
    protected HistoryService historyService;

    protected DataResponse getQueryResponse(HistoricProcessInstanceQueryRequest queryRequest, Map<String, String> allRequestParams) {
        HistoricProcessInstanceQuery query = historyService.createHistoricProcessInstanceQuery();

        // Populate query based on request
        if (queryRequest.getProcessInstanceId() != null) {
            query.processInstanceId(queryRequest.getProcessInstanceId());
        }
        if (queryRequest.getProcessInstanceIds() != null && !queryRequest.getProcessInstanceIds().isEmpty()) {
            query.processInstanceIds(new HashSet<String>(queryRequest.getProcessInstanceIds()));
        }
        if (queryRequest.getProcessDefinitionKey() != null) {
            query.processDefinitionKey(queryRequest.getProcessDefinitionKey());
        }
        if (queryRequest.getProcessDefinitionId() != null) {
            query.processDefinitionId(queryRequest.getProcessDefinitionId());
        }
        if (queryRequest.getProcessBusinessKey() != null) {
            query.processInstanceBusinessKey(queryRequest.getProcessBusinessKey());
        }
        if (queryRequest.getInvolvedUser() != null) {
            query.involvedUser(queryRequest.getInvolvedUser());
        }
        if (queryRequest.getSuperProcessInstanceId() != null) {
            query.superProcessInstanceId(queryRequest.getSuperProcessInstanceId());
        }
        if (queryRequest.getExcludeSubprocesses() != null) {
            query.excludeSubprocesses(queryRequest.getExcludeSubprocesses());
        }
        if (queryRequest.getFinishedAfter() != null) {
            query.finishedAfter(queryRequest.getFinishedAfter());
        }
        if (queryRequest.getFinishedBefore() != null) {
            query.finishedBefore(queryRequest.getFinishedBefore());
        }
        if (queryRequest.getStartedAfter() != null) {
            query.startedAfter(queryRequest.getStartedAfter());
        }
        if (queryRequest.getStartedBefore() != null) {
            query.startedBefore(queryRequest.getStartedBefore());
        }
        if (queryRequest.getStartedBy() != null) {
            query.startedBy(queryRequest.getStartedBy());
        }
        if (queryRequest.getFinished() != null) {
            if (queryRequest.getFinished()) {
                query.finished();
            } else {
                query.unfinished();
            }
        }
        if (queryRequest.getIncludeProcessVariables() != null) {
            if (queryRequest.getIncludeProcessVariables()) {
                query.includeProcessVariables();
            }
        }
        if (queryRequest.getVariables() != null) {
            addVariables(query, queryRequest.getVariables());
        }

        if (queryRequest.getTenantId() != null) {
            query.processInstanceTenantId(queryRequest.getTenantId());
        }

        if (queryRequest.getTenantIdLike() != null) {
            query.processInstanceTenantIdLike(queryRequest.getTenantIdLike());
        }

        if (Boolean.TRUE.equals(queryRequest.getWithoutTenantId())) {
            query.processInstanceWithoutTenantId();
        }

        return new HistoricProcessInstancePaginateList(restResponseFactory).paginateList(
                allRequestParams, queryRequest, query, "processInstanceId", allowedSortProperties);
    }

    protected void addVariables(HistoricProcessInstanceQuery processInstanceQuery, List<QueryVariable> variables) {
        for (QueryVariable variable : variables) {
            if (variable.getVariableOperation() == null) {
                throw new ActivitiIllegalArgumentException("Variable operation is missing for variable: " + variable.getName());
            }
            if (variable.getValue() == null) {
                throw new ActivitiIllegalArgumentException("Variable value is missing for variable: " + variable.getName());
            }

            boolean nameLess = variable.getName() == null;

            Object actualValue = restResponseFactory.getVariableValue(variable);

            // A value-only query is only possible using equals-operator
            if (nameLess && variable.getVariableOperation() != QueryVariableOperation.EQUALS) {
                throw new ActivitiIllegalArgumentException("Value-only query (without a variable-name) is only supported when using 'equals' operation.");
            }

            switch (variable.getVariableOperation()) {

                case EQUALS:
                    if (nameLess) {
                        processInstanceQuery.variableValueEquals(actualValue);
                    } else {
                        processInstanceQuery.variableValueEquals(variable.getName(), actualValue);
                    }
                    break;

                case EQUALS_IGNORE_CASE:
                    if (actualValue instanceof String) {
                        processInstanceQuery.variableValueEqualsIgnoreCase(variable.getName(), (String) actualValue);
                    } else {
                        throw new ActivitiIllegalArgumentException("Only string variable values are supported when ignoring casing, but was: "
                                + actualValue.getClass().getName());
                    }
                    break;

                case NOT_EQUALS:
                    processInstanceQuery.variableValueNotEquals(variable.getName(), actualValue);
                    break;

                case LIKE:
                    if (actualValue instanceof String) {
                        processInstanceQuery.variableValueLike(variable.getName(), (String) actualValue);
                    } else {
                        throw new ActivitiIllegalArgumentException("Only string variable values are supported for like, but was: "
                                + actualValue.getClass().getName());
                    }
                    break;

                case LIKE_IGNORE_CASE:
                    if (actualValue instanceof String) {
                        processInstanceQuery.variableValueLikeIgnoreCase(variable.getName(), (String) actualValue);
                    } else {
                        throw new ActivitiIllegalArgumentException("Only string variable values are supported for like, but was: "
                                + actualValue.getClass().getName());
                    }
                    break;

                case GREATER_THAN:
                    processInstanceQuery.variableValueGreaterThan(variable.getName(), actualValue);
                    break;

                case GREATER_THAN_OR_EQUALS:
                    processInstanceQuery.variableValueGreaterThanOrEqual(variable.getName(), actualValue);
                    break;

                case LESS_THAN:
                    processInstanceQuery.variableValueLessThan(variable.getName(), actualValue);
                    break;

                case LESS_THAN_OR_EQUALS:
                    processInstanceQuery.variableValueLessThanOrEqual(variable.getName(), actualValue);
                    break;

                default:
                    throw new ActivitiIllegalArgumentException("Unsupported variable query operation: " + variable.getVariableOperation());
            }
        }
    }
}
